This invention relates to polyurethane and/or polyurea polymers, particularly polyurethane and/or polyurea polymers prepared from high equivalent weight polyether polyahls having low levels of terminal unsaturation.
Polyurethane and/or polyurea polymers are conventionally prepared by reacting a polyisocyanate with one or more active hydrogen-containing compounds (hereinafter called "polyahls"). In the preparation of elastomeric polyurethanes and flexible polyurethane foams, the polyahl often comprises a high equivalent weight polyether which is prepared by polymerizing an alkylene oxide, an epihalohydrin or tetrahydrofuran in the presence of a polyhydric initiator to form a polyfunctional polymer.
Although the patent literature describes these polyether polyahls as broadly having equivalent weights of up to 6000 or more, in actual practice the equivalent weight of the polyether polyols used has rarely exceeded about 2000. One reason for this limitation is that higher alkylene oxides isomerize during their polymerization, forming terminal allylic unsaturation which both reduces the functionality of the polyether and terminates chain growth. It has therefore been prohibitively expensive to provide very high equivalent weight polyether polyahls of desired functionality. In addition, the lower functionality of the high equivalent weight polyethers causes polyurethane and/or polyurea polymers prepared therefrom to have relatively poor properties.
It would therefore be desirable to provide a polyurethane and/or polyurea polymer having good properties which is prepared from a high equivalent weight polyether polyol.